Improved stator assembly for progressive cavity pumping systems

ABSTRACT

A stator for use in a progressive cavity pump is provided, comprising a housing having a suction end and a discharge end, and an elastomeric liner disposed within the housing that defines a passageway for receiving a rotor of the pump. The elastomeric liner comprises a reinforced component that is proximate to the discharge end and that provides a landing surface to resist passage of a rotor head through the passageway.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a national stage application under 35 U.S.C. §371(c)of prior filed, co-pending PCT application serial numberPCT/US2014/048524, filed on Jul. 29, 2014, which claims priority to U.S.Provisional Patent Application Ser. No. 61/861,802, titled “IMPROVEDSTATOR ASSEMBLY FOR PROGRESSIVE CAVITY PUMPING SYSTEMS”, filed Aug. 2,2013. The above-listed applications are herein incorporated byreference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO APPENDIX

Not applicable.

BACKGROUND OF THE INVENTION

Embodiments of the invention relate generally to pumping equipment; andmore specifically related to an improved stator assembly for use withprogressive cavity and similar pumps, and a downhole pump assemblyincluding the improved stator.

Description of the Related Art

A progressive cavity or eccentric screw pump is generally known in theart and is suitable for many applications, including oil production. Asis well understood by those skilled in the art, a progressive cavitypump assembly includes a stator and rotor that engage with each other todefine cavities for receiving the material to be pumped. In an oilproduction application, the assembly is suspended in a wellbore incommunication with a reservoir. Fluid from the reservoir flows into thewellbore and enters the pump assembly at an entrance of the stator,entering a cavity defined cooperatively by the rotor and stator. As therotor rotates relative to the stator, the defined cavities effectively“travel” along the axis of the assembly, carrying the fluid upwards.

The capacity and efficiency of the progressive cavity pump assembly isdetermined at least in part by the correct engagement of the rotor withthe stator. For instance, if the rotor is not fully extended through thestator, then the overall capacity of the pump assembly is reduced.However, in oilfield and similar applications, the positioning of therotor in the stator must be accomplished remotely.

A prior art solution to the problem of aligning the rotor with thestator was to affix a tag plate or bar to the intake or suction end ofthe stator. The tag plate or bar provided an obstruction across theintake opening of the stator. When the rotor was lowered into thestator, the lower end of the rotor would pass through the stator andeventually contact the tag plate or bar. The contact could be detectedby a weight indicator at the surface. Once contact had been achieved,the rotor could be retracted towards the surface by an appropriateamount, typically computed based on expected tension on the rod string.A disadvantage of the prior art tag plate, however, is that it couldrestrict slurries and solids from entering into the stator opening. Itcould also obstruct the passage of wireline tools that the operatorwishes to lower into the wellbore, past the lower end of the stator.Moreover, the lower end of the rotor may strike or drag across the tagplate or bar during installation, potentially damaging the rotor orcoating.

Another proposed solution is the use of a tag shoulder provided in a subthat is mounted to the tubing string above the stator, which cooperateswith a stop mounted to the rod string on which the rotor is suspended,as described in Canadian Patent No. 2,567,989. As the rotor is lowered,the stop on the rod string comes into contact with the shoulder mountedon the tubing string, to land the rotor. Another proposed solution is atop-tag coupling assembly described in Canadian Patent No. 2,612,326, inwhich the rotor head, which is larger than the helical portion of therotor, lands on a narrowing shoulder section of the tubing string collaror coupler, also located above the stator. However, because the shoulderis positioned in the tubing string or connector above the stator, thesesolutions present an additional obstacle to the rotor as it is loweredthrough the tubing string or connector above the stator. A metalshoulder may cause scratches or other damage to the rotor as it descendspast the shoulder.

Embodiments of the invention disclosed and taught herein are directed topumping equipment, and in particular to an improved stator assembly foruse with progressive cavity and similar pumps, and a downhole pumpassembly including the improved stator.

BRIEF SUMMARY OF THE INVENTION

The objects described above and other advantages and features of theinvention are incorporated in the application as set forth herein, andthe associated drawings, related to systems an improved stator assemblyfor use with progressive cavity and similar pumps, and a downhole pumpassembly including the improved stator.

In accordance with a first embodiment of the present disclosure, astator for use in a progressive cavity pump is disclosed. The statortypically includes a housing having a suction end and a discharge end,an elastomeric liner disposed within the housing and defining apassageway for receiving a rotor of the progressive cavity pump. Thepassageway typically comprises a reinforced component proximate to thedischarge end of the housing. The reinforced component of the passagewaydefines an opening smaller in dimension than a head of the rotor. Thereinforced component of the stator may define a shoulder adapted forcontact with the rotor head. The reinforced component of the stator maycomprise at least one pin, may be formed integrally within the housing,may be mounted on the interior of the housing, or may be mounted throughthe housing. The elastomeric liner is typically deformable to provide acompression fit between the stator and a rotor to define discretecavities between the stator and rotor. The elastomeric liner may extendfrom the suction end of the stator and terminates before the dischargeend of the stator. The reinforced component of the stator may becomprised of a material with greater resistance to deformity than theelastomeric liner.

In accordance with another embodiment of the present disclosure, astator for use in a progressive cavity pump is disclosed. The statortypically comprises a housing comprising a wall and at least onereinforcing component extending from an interior face of the wall. Thestator may further comprise an elastomeric liner disposed within thehousing and extending over the at least one reinforcing component. Theelastomeric liner may further define a passageway for a rotor of theprogressive cavity pump. A component of the elastomeric liner may extendover the at least one reinforcing component defining a shoulder forengaging a rotor head of the rotor. The at least one reinforcingcomponent is typically proximate to the discharge end of the housing.The reinforcing component may comprise of at least one pin, may beformed integrally with the housing, may be mounted on the interior ofthe housing, or may be mounted through the housing. The elastomericliner may extend from the suction end of the stator and end before thedischarge end of the stator.

In accordance with another embodiment of the present disclosure, amethod of operating a progressive cavity pump is disclosed. Theprogressive cavity pump may comprise any stator includes those describedherein. The stator typically comprises a housing having a suction endand a discharge end. The stator may comprise an elastomeric linerdisposed within the housing and defining a passageway for receiving arotor of the progressive cavity pump. The elastomeric liner may compriseat least one reinforced component proximate to the discharge end, the atleast one reinforced component providing a landing surface to resistpassage of a rotor head of the rotor through the passageway. The methodtypically comprises installing the stator in a wellbore, lowering therotor for the progressive cavity pump on a rod string into the statoruntil a lower surface of the rotor head of the rotor contacts theshoulder of the stator, and on detecting the contact, raising the rotoron the rod string to a predefined position. The method may furthercomprise rotating the rotor in an eccentric rotation along the interiorsurface of the stator. The method may further include pumping materialthrough the progressive cavity pump. The method may further includepumping material through an intake end of the progressive cavity pumpand through an open cavity defined by the rotor and stator.

BRIEF DESCRIPTION OF THE DRAWINGS

The following figures form part of the present specification and areincluded to further demonstrate certain aspects of the presentinvention. Embodiments of the invention may be better understood byreference to one or more of these figures in combination with thedetailed description of specific embodiments presented herein.

FIG. 1 illustrates a perspective view of a segment of a downhole pumpassembly including a collar, stator assembly, and rotor.

FIG. 2A illustrates a top view of the segment of the downhole pumpassembly of FIG. 1.

FIG. 2B illustrates a sectional view of the assembly of FIG. 1 in theplane 2B indicated in FIG. 2A.

FIG. 2C illustrates a plan sectioned view of the assembly of FIG. 1 inthe plane 2C indicated in FIG. 2B.

While embodiments of the invention disclosed herein are susceptible tovarious modifications and alternative forms, only a few specificembodiments have been shown by way of example in the drawings and aredescribed in detail below. The figures and detailed descriptions ofthese specific embodiments are not intended to limit the breadth orscope of the inventive concepts or the appended claims in any manner.Rather, the figures and detailed written descriptions are provided toillustrate the inventive concepts to a person of ordinary skill in theart and to enable such person to make and use the inventive concepts.

DETAILED DESCRIPTION

The Figures described above and the written description of specificstructures and functions below are not presented to limit the scope ofwhat Applicants have invented or the scope of the appended claims.Rather, the Figures and written description are provided to teach anyperson skilled in the art to make and use the inventions for whichpatent protection is sought. Those skilled in the art will appreciatethat not all features of a commercial embodiment of the inventions aredescribed or shown for the sake of clarity and understanding. Persons ofskill in this art will also appreciate that the development of an actualcommercial embodiment incorporating aspects of the present inventionswill require numerous implementation-specific decisions to achieve thedeveloper's ultimate goal for the commercial embodiment. Suchimplementation-specific decisions may include, and likely are notlimited to, compliance with system-related, business-related,government-related and other constraints, which may vary by specificimplementation, location and from time to time. While a developer'sefforts might be complex and time-consuming in an absolute sense, suchefforts would be, nevertheless, a routine undertaking for those of skillin this art having benefit of this disclosure. It must be understoodthat the inventions disclosed and taught herein are susceptible tonumerous and various modifications and alternative forms. Lastly, theuse of a singular term, such as, but not limited to, “a,” is notintended as limiting of the number of items. Also, the use of relationalterms, such as, but not limited to, “top,” “bottom,” “left,” “right,”“upper,” “lower,” “down,” “up,” “side,” and the like are used in thewritten description for clarity in specific reference to the Figures andare not intended to limit the scope of the invention or the appendedclaims.

Applicants have created an improved stator assembly for use withprogressive cavity and similar pumps, and a downhole pump assemblyincluding the improved stator. The design and operation of progressivecavity pumps is generally known in the art. As will be understood bythose skilled in the art, a progressive cavity pump assembly ascontemplated herein includes a stator, typically cylindrical in shapebut can embody alternate forms, with an interior surface defined tocooperate with a rotor so as to define one or more cavities between theinterior surface of the stator and a surface of the rotor. Generally, anexterior surface of the rotor defines a helical shape and the interiorsurface of the stator defines a double helical passageway or bore. Thetypical shape is generally helical but variations are normal. When therotor is engaged in the bore of the stator, the interior surface of thestator and exterior surface of the rotor contact to define cavities forreceiving the material to be pumped. Typically, the rotor ismanufactured of a rigid material such as an alloy steel or stainlesssteel that would typically include a wear resistant coating, whileinterior surface of the stator is provided by an elastomeric lining orinsert in a metal stator housing. Being deformable, the elastomericsurface of the stator can provide for a compression fit between thestator and rotor so as to define discrete cavities. The selection ofsuitable materials for the stator and rotor components, as well as theother components of the entire pumping system, will be known to those inthe art.

The material to be pumped enters an intake or suction end of the pumpassembly, e.g., a suction end of the stator, and is typically receivedin an open cavity defined by the rotor and stator. The rotor istypically connected at a rotor head end, using couplings or othersuitable connection means, on a drive shaft assembly connected to adrive system that moves the rotor in an eccentric rotation along theinterior surface of the stator. As the rotor rotates, the definedcavities effectively “travel” along the axis of the assembly. Thematerial in the cavities is thus carried along the axis of the stator toa discharge end of the stator.

In an oil production application, the material to be pumped is typicallyfluid, which can have liquid and gaseous components; however, thoseskilled in the art will appreciate that progressive cavity pumps, andthe improvements discussed herein, can also be used in conjunction withslurries, solid matter, water, and gas. In an oil well application, thestator is typically suspended on a string of tubing within a wellbore incommunication with a reservoir. The string of tubing itself may consistof an integral piece of tubing, or several segments screwed or otherwisejoined together. The stator is fixed to the end of the tubing string bya collar. The interior diameters of the tubing string and the collar, aswell as the stator itself, are dimensioned to admit passage of the rotorand any wireline tools that may be employed in the well. The drive shaftassembly on which the rotor is mounted may be a rod string, typicallycomprising segments of steel rods that are joined by screw couplings.The rotor, on its drive shaft, is lowered through the tubing string andinto the stator.

The pump assembly can be located several thousand metres below thesurface in an oilfield application. It can thus be appreciated that theactual mounting of the rotor within the stator occurs at a locationremote from the operator, and that visual inspection of the pumpassembly to ascertain that the rotor is correctly positioned within thestator is typically not possible. Generally, for optimum operation, theend of the rotor is expected to be substantially level with the suctionend of the stator, and the rod string under tension; if the rotor endssome distance from the suction end, then the pumping capacity andefficiency of the pump assembly may be reduced. The position of therotor within the pump assembly varies according to the load on theassembly. As fluid enters the assembly, its weight causes the rod stringto stretch, thus altering the final position of the rotor.

Accordingly, the embodiments described herein provide an alternativealignment mechanism for a progressive cavity pump assembly that permitsthe operator to correctly position the rotor within the stator. In oneexample, tag pins are provided within the stator itself proximate towhat may be considered the discharge end of the stator, which is the endopposing the suction end of the stator.

Turning now to the figures, FIG. 1 depicts a perspective view of aportion of a progressive cavity pump subassembly 100, comprising astator 50 with a rotor 30 disposed within, and FIG. 2A illustrates a topview of the segment of the downhole pump assembly of FIG. 1. It will beunderstood by those skilled in the art that the examples depicted in theaccompanying figures are only representative of an actual progressivecavity pump subassembly 100 and are not to scale; for instance the rotor30 and stator 50 can be considered to be segments of a full rotor andstator, respectively, truncated for ease of illustration. The stator 50is coupled to the tubing string (not shown) at the discharge end 54 ofthe stator 50, either directly or by means of the collar 10 shown in thedrawings. The collar 10 in turn is coupled to the tubing string (notshown) of the complete downhole assembly. Coupling may be accomplishedusing any suitable means known in the art. The elastomeric lining 55 inthe stator 50 is not visible in FIG. 1. Elastomeric lining 55 may beseen in FIGS. 2B and 2C, and is discussed in further detail below.However, as part of the housing 53, at least one reinforcing component,here shown as one of pins 60, provide reinforcement and/or an anchor forthe elastomeric lining 55. Pins 60 may be more readily seen in FIG. 2B,and are discussed in further detail below.

FIG. 2B provides a cross-sectional view of the progressive cavity pumpsubassembly 100 of FIG. 1. The collar 10 is coupled to the stator 50 atthe discharge end 54 of the stator 50. The collar 10 is generally acylindrical walled element. As mentioned above, the collar 10 is mountedto the tubing string (not shown). An inner diameter of the collar 10, asdefined by interior surface 12, is large enough to permit passage of therotor 30 therethrough. Fluid, or whatever material is being pumped, maypass from the rotor 30-stator 50 assembly into the collar 10 through thetubing to an outlet of the pumping system.

The stator 50 comprises a housing 53. Throughout a substantial part ofthe housing 53, an elastomeric liner, surface or wall 55 is provided.The elastomeric liner 55 in this example is a wall with a varyingthickness profile that defines the interior surface 56 of the stator 50which, as described above, provides the appropriate helical passageway44 for the progressive cavity pump. The typical shape of passageway 44is generally helical but variations are normal. The helically-shapedpassageway 44 can extend to or near the suction end 52 of the stator 50,but may end before the discharge end 54. Accordingly, the elastomericliner 55 does not extend all the way to the end 54 of the stator 50, butterminates before the end. It will be understood, however, in othercollar-stator configurations, the elastomeric liner 55 may extendfurther along the interior of the stator 50. The elastomeric liner 55 ismay be symmetrical at both the suction and discharge ends of the stator.

Within the elastomeric liner 55, one or more reinforcing components 60are provided, in this case pins on opposite sides of the bore. Thereinforcing components 60 extend at least from the interior face of thehousing 53 into the elastomeric liner 55 and can be formed ormanufactured of steel or similar material to that used for the housing53 or collar 10. Generally, the reinforcing components 60 are formed ofa material with greater resistance to deformity than the elastomericliner 55. The reinforcing components 60 in the example illustrated inthe drawings are in the form of rounded pins or protrusions extendingthrough the housing 53 and into the interior of the housing 53. The pins60 provide a reinforced, substantially level surface within the stator(i.e., in a plane substantially perpendicular to the axis of thestator). Here, the reinforcing components 60 are formed separately fromthe housing 53 and are inserted through boreholes or apertures 62provided in the housing 53, and are secured in place, for instance bywelding. Turning briefly to FIG. 2C, which illustrates a cross-sectionalview of the progressive cavity pump subassembly 100 taken along plane 2Cindicated in FIG. 2B, it can be seen that the exterior surface 61 of thereinforcing components 60 is substantially flush with the exteriorsurface of the stator housing 53.

Returning to FIG. 2B, the reinforcing components 60 form part of thestator structure and are located within the elastomeric liner 55defining the interior surface of the stator 50, and in this example, theinterior surface 56 of the stator 50 defined by the elastomeric liner 55substantially maintains its helical configuration even at the reinforcedsections 60 of the elastomeric liner 55, where the elastomeric liner 55includes the reinforcing components 60. The elastomeric liner 55 extendsover and incorporates the reinforcing components 60, generallyconforming to the shape of the components 60, and terminates at thehousing 53 above the reinforcing components 60.

In other examples, not shown in the figures, the reinforcing components60 may be formed integrally with the housing 53 or are mounted on theinterior of the housing 53 rather than through the housing 53. It willbe appreciated by those skilled in the art that the rounded pinconfiguration of the reinforcing components 60 is not necessary, andthat other shapes or configurations may be employed. It can be seen,though, that in this example, the reinforcing components 60 do notsubstantially interrupt the profile of the helical passageway 44typically employed in progressive cavity pumps. This can be seen morereadily in FIG. 2A, which is a top view of the progressive cavity pumpsubassembly 100, as well as in FIG. 2C. The elastomeric liner 55, inaddition to defining the helical passageway 44 by its interior surface56, also defines an opening 65 in its upper surface or shoulder 57. Asis conventional in the art, the opening 65 is generally shaped to permitthe required motion of the rotor 30 as it is moved and rotated on itsdrive shaft (not shown). The helical passageway 44 is defined by theinterior surface of the elastomeric liner 55, and not the reinforcingcomponents 60. The reinforcing components 60 thus do not unduly obstructthe passage of the rotor 30 or wireline tools into the stator 50.However, because the elastomeric liner 55 is now provided withreinforcement by the reinforcing components 60, the upper surface 57 canfunction as a landing surface or tag shoulder 57 that resists downwardmotion of the rotor head 34 without substantial deformity of the uppersurface 57 or the helical passageway 44 defined by the elastomeric liner55. Landing of the rotor head 34 on the reinforced stator upper surface57 provides for proper alignment and positioning of the rotor 30 withinthe stator 50.

Returning to FIG. 2B, an appropriately dimensioned rotor 30 is showninserted in the collar 10 and stator 50. The rotor 30 includes a rotorhead 34 and a helical portion 40. The rotor head 34 is typically coupledto the rod string, not shown for clarity in the figures. The rotor head34 is enlarged compared to the minor diameter of the helical passageway44, and furthermore has a dimension greater than the distance betweenthe reinforced portions 60 of the elastomeric liner 55. Thus, when therotor 30, mounted on its rod string or drive shaft (not shown), islowered as far as possible into the collar 10-stator 50 assembly, thelower surface 36 of the rotor head 34 will contact the upper surface orshoulder 57 defined by the elastomeric liner 55. The elastomeric liner55, being reinforced by the reinforcing components 60 at or near theupper surface 57, is sufficiently rigid to function as a tag shoulder.Contact between the rotor head 34 and the reinforced elastomeric liner55 can be detected using a weight indicator or other means known in theart. When this contact between the rotor head 34 and the stator 50 isdetected, the rotor 30 can then be raised to the proper position asdetermined by the operator based on this reference point, and the rodstring mounted to the drive system. In operation, a helix passageway 44is formed by the cooperation of the interior surface 56 of theelastomeric liner 55 and the exterior surface 41 of the helical portion40 of the rotor 30.

It will be appreciated from the foregoing that by reinforcing theelastomeric liner 55 of the stator 50 in this manner, it is notnecessary to provide a separate tag plate or bar at the bottom of thestator 50, thus avoiding the prior art problems mentioned above.Furthermore, the reinforcement described herein effectively provides thestator 50 with an integral tag shoulder or surface 57 without the needfor retrofitting or adapting the collar 10 to have an abutment or shelfto provide the tagging function, or installing a stop or other componenton the rod string to cooperate with the adapted collar. Since thereinforcing components 60 are encased in the elastomeric liner 55, therisk of damage to the rotor 30 as it is lowered into the stator 50 ismitigated. The adaptation of the collar 10 or rod string (not shown) inthis manner presents the possible risk of changing the static or dynamiccharacteristics of those components.

Various embodiments of the present invention having been thus describedin detail by way of example, it will be apparent to those skilled in theart that variations and modifications may be made without departing fromthe invention. The invention includes all such variations andmodifications as fall within the scope of the appended claims.Throughout the specification, terms such as “may” and “can” are usedinterchangeably and use of any particular term should not be construedas limiting the scope or requiring experimentation to implement theclaimed subject matter or embodiments described herein.

The proceeding examples are included to demonstrate preferredembodiments of the inventions. It should be appreciated by those ofskill in the art that the techniques disclosed in the examples aboverepresent techniques discovered by the inventors to function well in thepractice of the inventions, and thus can be considered to constitutepreferred modes for its practice. However, those of skill in the artshould, in light of the present disclosure, appreciate that many changescan be made in the specific embodiments which are disclosed and stillobtain a like or similar result without departing from the scope of theinventions.

Other and further embodiments utilizing one or more aspects of theinventions described above can be devised without departing from thespirit of Applicants' invention. Further, the various methods andembodiments of the methods of manufacture and assembly of the system, aswell as location specifications, can be included in combination witheach other to produce variations of the disclosed methods andembodiments. Discussion of singular elements can include plural elementsand vice-versa.

The order of steps can occur in a variety of sequences unless otherwisespecifically limited. The various steps described herein can be combinedwith other steps, interlineated with the stated steps, and/or split intomultiple steps. Similarly, elements have been described functionally andcan be embodied as separate components or can be combined intocomponents having multiple functions.

The inventions have been described in the context of preferred and otherembodiments and not every embodiment of the invention has beendescribed. Obvious modifications and alterations to the describedembodiments are available to those of ordinary skill in the art. Thedisclosed and undisclosed embodiments are not intended to limit orrestrict the scope or applicability of the invention conceived of by theApplicants, but rather, in conformity with the patent laws, Applicantsintend to fully protect all such modifications and improvements thatcome within the scope or range of equivalent of the following claims.

What is claimed is:
 1. A stator for use in a progressive cavity pump,the stator comprising: a housing having a suction end and a dischargeend; and an elastomeric liner disposed within the housing and defining apassageway for receiving a rotor of the progressive cavity pump, thepassageway comprising a reinforced component proximate to the dischargeend of the housing, and the reinforced component of the passagewaydefining an opening smaller in dimension than a rotor head of the rotor.2. The stator of claim 1, wherein the reinforced component defines ashoulder adapted for contact with the rotor head.
 3. The stator of claim1, wherein the reinforced component of the passageway comprises at leastone pin.
 4. The stator of claim 1, wherein the reinforced component ofthe passageway is formed integrally with the housing.
 5. The stator ofclaim 1, wherein the reinforced component of the passageway is mountedon the interior of the housing.
 6. The stator of claim 1, wherein thereinforced component of the passageway is mounted through the housing.7. The stator of claim 1, wherein the elastomeric liner is deformable toprovide a compression fit between the stator and a rotor to definediscrete cavities between the stator and rotor.
 8. The stator of claim1, wherein the elastomeric liner extends from the suction end of thestator and terminates before the discharge end of the stator.
 9. Thestator of claim 1, wherein the reinforced component is comprised of amaterial with greater resistance to deformity than the elastomericliner.
 10. A stator for use in a progressive cavity pump, the statorcomprising: a housing comprising a wall and at least one reinforcingcomponent extending from an interior face of the wall; and anelastomeric liner disposed within the housing and extending over the atleast one reinforcing component, the elastomeric liner defining apassageway for a rotor of the progressive cavity pump, a portion of theelastomeric liner extending over the at least one reinforcing componentdefining a shoulder for engaging a rotor head of the rotor.
 11. Thestator of claim 10, wherein the reinforcing component is proximate tothe discharge end of the housing.
 12. The stator of claim 10, whereinthe at least one reinforcing component comprises at least one pin. 13.The stator of claim 10, wherein the at least one reinforcing componentis formed integrally with the housing.
 14. The stator of claim 10,wherein the at least one reinforcing component is mounted on theinterior of the housing.
 15. The stator of claim 10, wherein the atleast one reinforcing component is mounted through the housing.
 16. Thestator of claim 10, wherein the elastomeric liner extends from thesuction end of the stator and ends before the discharge end of thestator.
 17. A method of operating a progressive cavity pump, theprogressive cavity pump comprising, a stator comprising, a housinghaving a suction end and a discharge end; and an elastomeric linerdisposed within the housing and defining a passageway for receiving arotor of the progressive cavity pump the elastomeric liner comprising atleast one reinforced component proximate to the discharge end, the atleast one reinforced component providing a landing surface to resistpassage of a rotor head of the rotor through the passageway the methodcomprising: installing the stator in a wellbore; lowering the rotor forthe progressive cavity pump on a rod string into the stator until alower surface of the rotor head of the rotor contacts the shoulder ofthe stator; and on detecting the contact, raising the rotor on the rodstring to a predefined position.
 18. The method of claim 17, furthercomprising rotating the rotor in an eccentric rotation along theinterior surface of the stator.
 19. The method of claim 17, furthercomprising pumping material through the progressive cavity pump.
 20. Themethod of claim 19, wherein pumping material through the progressivecavity pump further comprises pumping material through an intake end ofthe progressive cavity pump and through an open cavity defined by therotor and stator.